In the field of products used by consumers today, unwanted sounds or other noises emanating from such a product create an unpleasant environment for the consumer. Such an unwanted noise is particularly noticeable in environments that include a resilient-like product coming in contact with a relatively movable hard surface such as a metal part. This relative movement generates friction between these surfaces that often leads to clearly audible sounds that simply may be referred to as "squeaks" by the general public. Of course it is recognized that lubrication between these contacting surfaces minimizes, if not removes, the friction and avoids any further unwanted noise or squeaks. However in many products, particularly those in the automobile industry, there are so many instances where the surface of a resilient product contacts a relatively moving metal surface that providing the necessary lubrication at the precise location of the friction is not only not practical but usually impossible.
In particular, it has been found that in the automotive vehicle field, inner stabilizer bar bushings for use with elongated stabilizer bars often generate unwanted noises and squeaking because of the inherent stabilizer bar torsional action that generates relative movement. Further, a front stabilizer bar and cushion, also used in the automotive vehicle field, functions to help manage the stabilizer bar's torsional, conical, radial and axial actions but which often have been found to generate noise and squeaking. In each of the above instances the part or element in contact with the metal surface must be sufficiently durable for the life of the vehicle.
Eliminating friction causing squeaks is not limited to the automotive field. Products that would relieve the unwanted squeaks attendant to the inherent friction arising from the incorporation of bushings or other cushion like resilient products, for example, that are in intimate contact with movable surfaces would clearly fill a huge void in the art. For instance, any contact between a resilient element and a hard metal surface is subject to producing a squeak that external grease or other lubricant may be difficult, if not impossible, to be provided in every location where such frictional contact may occur.
Accordingly, there is a significant practical need in the art for a resilient product such as a thermoplastic polyurethane that possesses self-lubricating capabilities to continually provide lubricant that has the effect of minimizing, reducing or even eliminating friction that would otherwise produce unwanted noises or squeaking.